Chances are that you need a unique node ID for each target device. One way to get such an ID is by defining the symbol `FLOCKLAB_NODE_ID` in your code:
Chances are that you need a unique node ID for each target device. One way to get such an ID is by defining the symbol `FLOCKLAB_NODE_ID` in your code:
```
```
// must be global (variable will be placed into the .data section)
// must be global (variable will be placed into the .data section)
volatile uint16_t FLOCKLAB_NODE_ID = 0xbeef; // any value is ok, will be overwritten by FlockLab
uint16_t FLOCKLAB_NODE_ID = 0xbeef; // any value is ok, will be overwritten by FlockLab
```
```
FlockLab will then automatically change this value to the target ID (if specified, otherwise the observer ID is used) before uploading the image to the targets.
FlockLab will then automatically change this value to the target ID (if specified, otherwise the observer ID is used) before uploading the image to the targets.
You can use `objdump` to check whether the symbol is included in the binary:
You can use `objdump` to check whether the symbol is included in the binary: